Jacking device

ABSTRACT

A jacking device consisting of first and second tubular members which are telescoped with respect to one another and provided with a simple and inexpensive means for adjusting the length thereof. The device also includes a third tubular member telescoped with respect to the first tubular member and a spring for urging the third tubular member to an extended position with respect to the first tubular member. Simplicity in the adjustment means is achieved by forming a series of longitudinally spaced passages in the second tubular member and forming a support shoulder which includes an annular collar on the other tubular member at one end thereof. The adjustment device consists of a bracket and a lever arm pivotally mounted on the bracket. In use, one end of the lever arm is located within one of the longitudinal passages of the second tubular member and the free end of the bracket is mounted on the support shoulder of the first tubular member. The lever arm is then pivoted about the fulcrum mounting on the bracket to cause the free end of the lever arm to engage the second tubular member and to move the second tubular member outwardly with respect to the first tubular member, the bracket acting as a support for the fulcrum point of the lever arm. A simple mounting for the third telescopic member is achieved by forming rearwardly inwardly directed waist portions in the first tubular member and the third tubular member and locating a pair of discs outwardly from each waist member and retaining each disc against a predetermined movement with respect to one another by extending a bolt therebetween.

United States Patent [191 Elias JACKING DEVICE [75] Inventor: Murray A.Elias, lslington, Ontario,

Canada [73] Assignee: Dell Holdings Limited, Rexdale,

Ontario, Canada [22] Filed: Aug. 28, 1973 [21] Appl. No.: 392,208

Primary Examiner-Othell M. Simpson Attorney, Agent, orFirm-Fetherstonhaugh & Co.

[57] ABSTRACT A jacking device consisting of first and second tubularmembers which are telescoped with respect to one an- Nov. 19, 1974 otherand provided with a simple and inexpensive means for adjusting thelength thereof. The device also includes a third tubular membertelescoped with respect to the first tubular member and a spring forurging the third tubular member to an extended position with respect tothe first tubular member. Simplicity in the adjustment means is achievedby forming a series of longitudinally spaced passages in the secondtubular member and forming a support shoulder which includes an annularcollar on the other tubular member at one end thereof. The adjustmentdevice consists of a bracket and a lever arm pivotally mounted on thebracket. In use, one end of the lever arm is located within one of thelongitudinal passages of the second tubular member and the free end ofthe bracket is mounted on the support shoulder of the first tubularmember. The lever arm is then pivoted about the fulcrum mounting on thebracket to cause the free end of the lever arm to engage the secondtubular member and to move the second tubular member outwardly withrespect to the first tubular member, the bracket acting as a support forthe fulcrum point of the lever arm. A simple mounting for the thirdtelescopic member is achieved by forming rearwardly inwardly directedwaist portions in the first tubular member and the third tubular memberand locating a pair of discs outwardly from each waist member andretaining each disc against a predetermined movement with respect to oneanother by extending a bolt therebetween.

11 Claims, 7 Drawing Figures PATENTEL NOV 1 9 I974 SHEET 1 UP 2 FIG. 7

JACKING DEVICE This invention relates to a jacking device. Inparticular, this invention relates to a jacking device suitable for usein the construction industry.

The jacking devices currently used in the construction industry includetwo tubular elements which are telescoped with respect to one anotherand adjustable in length by moving one element with respect to theother. The adjustment means used for adjusting the length of thetelescoping member usually consists of a jacking nut which is threadablymounted with respect to one of the telescoping elements so that rotationof the nut in one direction causes expansion of the telescoping elementwhile rotation in the other direction causes contraction of thetelescoping element. A major disadvantage of this construction is thefact that the exposed threaded portions of the adjustment elementsfrequently become damaged in use so that difficulty is experienced inattempting to move the adjustment nuts. A further disadvantage of thisadjustment nut construction is the fact that it does not include anyprovision for a rapid action course adjustment.

In another form of jacking device, it is well known to form a pluralityof passageways opening through one of the telescoping elements atlongitudinally spaced intervals to receive a locking pin to retain thejacking device in a predetermined position. The difficulty with thisconstruction is that it requires considerable physical effort tomanipulate the jacking device into an extended position in which it isloaded prior to the location of the locking pin. Furthermore, the amountof the load which may be applied to the jacking device may be too greatto permit manual adjustment of the telescoping elements.

In order to ensure that a jacking device, such as the jacking devicesused in the construction industry, is not dislodged when the loadsupported by the jacking device is raised a short distance, it isdesirable to provide a mechanism which is resiliently deformable tocompensate for periodic variations in a jacking height. Difficulty hasbeen experienced in providing a simple and effective structure formounting the resiliently adjustable elements with respect to the jackingdevice.

The present invention provides a simple and inexpensive jacking devicefor use in the construction industry which includes adjustment means fortelescoping one element with respect to the other element under loadconditions.

The present invention also provides a simple and efficient structure formounting a resiliently compressible unit for accommodating variations inlength of the loaded jacking device.

According to an embodiment of the present invention, a jacking deviceconsists of a first tubular member having a second tubular membertelescopically mounted therein and projecting outwardly from one endthereof. Anadjustment means is provided for adjusting the position ofthe second tubular member with respect to the first tubular member. Theadjustment means consists of a bracket member, a lever member andfulcrum means pivotally mounting the lever member with respect to thebracket member. The lever member has a first end projecting outwardlyfrom one side of the fulcrum and a second end projecting outwardly fromthe other side of the fulcrum. The outer end of the bracket is mountableat one end of said first tubular member in a position with the fulcrummeans spaced outwardly from the first and second tubular means. Thesecond tubular member is provided with means for cooperating with thefirst end of said lever means whereby the second tubular member may betelescoped with respect to the first tubular member in response tomovement of the second end of the lever about said fulcrum means. Meansis also provided for locking the first tubular member with respect tothe second tubular member in a position to which the members aretelescoped by means of adjustment means.

The present invention also provides a jacking device as described abovehaving a third telescopically mounted element in the other end of saidfirst tubular member for movement between a first retracted position anda second extended position, and means for resiliently urging the thirdtubular member towards said extended position.

The invention will be more clearly understood after reference to thefollowing detailed specification read in conjunction with the drawingswherein:

FIG. 1 is a pictorial view illustrating a typical installation of a pairof jacking devices according to an embodiment of the present invention;

FIG. 2 is a partially sectioned side view of a jacking device accordingto an embodiment of the present invention;

FIG. 3 is a partial pictorial view illustrating the manner in which theadjustment means is mounted with respect to the telescoping elements;

FIG. 4 is a partially sectioned side view illustrating a first step inthe operation of the telescoping mechanism;

FIG. 5 is a view similar to FIG. 4 showing a further stage in thejacking operation;

FIG. 6 is a pictorial view of a modified form of adjustment bracket andlever assembly; and

FIG. 7 is a side view similar to FIG. 5 showing the adjustment device ofFIG. 6 in use.

With reference to FIG. 1 of the drawings, the reference numeral 10refers generally to a jacking device according to an embodiment of thepresent invention. The jacking device is used on a construction site forvarious purposes, including the supporting of a safety wall assembly 12or as a brace for an overhead wall or former 13.

As shown in FIGS. 1 and 2 of the drawings, the jacking devices 10 eachconsist of a first tubular member 14, a second tubular member 16 and athird tubular member 18. The second tubular member 16 and the thirdtubular member 18 are telescoped within opposite ends of the firsttubular member 14. The exposed ends of the second tubular member 16 andthe third tubular member 18 have end caps 20 located thereon to preventdirect contact between the tubular members 14 and 18 and'the structuresto be supported. The second tubular member 16 is formed with a first setof passages 22 which are located at longitudinally spaced intervalsalong the length thereof from adjacent the end which is to be telescopedwithin the first tubular member 14. The passages 22 extend throughdiametrically opposed portions of the wall of the second tubular member16 so that a locking pin 24 may extend therethrough and project fromopposite sides of the tubular member. A collar 46 is located at the endof the first tubular member and has an end free projecting radially inalignment with the end of the first tubular member and cooperatingtherewith to form a radially extending support surface for the bracketas will be described hereinafter. Small arcuate shaped recesses 26 areformed in the support surface at diametrically opposed location thereonto receive the ends of bracket 30 in use and to prevent circumferentialmovement of the bracket with respect to the first tubular member. Asecond row of passages 28 open through one side of the tubular member 16at the end which is telescoped within the first tubular member 14.

An adjustment device for adjusting the position of the first tubularmember with respect to the second tubular member comprises a bracket 30and a lever member 32 which is pivotably mounted with respect to thebracket by means of a fulcrum pin 34. The bracket 30 has a pair ofspaced apart arms 36 which are connected at their upper end by a bridgepiece 38. The arms 36 are disposed one on either side of the plane inwhich the lever 32 pivots about the fulcrum pin 34. The lever 32 has afirst end 40 projecting outwardly from one side of the bracket 30 and asecond end 42 projecting outwardly from the other side of the bracket30. A short upwardly directed tongue portion 44 is formed at the freeend of the first portion 40 of the lever 32.

When the jacking device of the present invention is to be used, it ismanually extended to its maximum height permitted by the enclosurewithin which it is mounted and the locking pin 24 is located in aposition extending through the passages 22 and resting in the supportsurface 25. If adjustment is required to increase the length of thejacking device, the adjustment means is mounted as shown in FIG. 3 ofthe drawings by locating the ends 36 of the bracket 34 in a position inwhich they are located in the recesses 26. The lever arm 42 is pivotedto a position with respect to the bracket 34 so that the tongue 44-onthe first end of the lever arm 32 may be located within a passage 28 ofthe second tubular member 16. The passage 28 in which the tongue 44 ismounted is preferably at the lowest level which the tongue 44 is able toengage. The lever arm 32 is then pivoted through the first elevatedposition shown in FIG. 4 to the second elevated position shown in FIG.5. In the position shown in FIG. 5, the second tubular member has beenextended out of the first tubular member by a length equal to thedistance between adjacent passages 22 in the second tubular member 16 sothat the locking pin 24 may be relocated, the lever arm 32 pivoted to aposition to enable the tongue 44 to engage the next lower passage 28 andthereafter the telescoping operation may be repeated.

FIG. 6 of the drawings illustrates a further embodiment of the inventionwherein the bracket 30a is in a different form from that illustrated inFIGS. 3 to 5 inclusive. The bracket 30 nevertheless retains thebifurcated end construction so that short arms 36a are provided whichagain engage the support surface 25 on opposite sides of the passages 28in which the locking pin 24 is located in use. FIG. 7 of the drawingsillustrates the manner in which the adjusting device of FIG. 6 is usedand it will be apparent that the manner of operation is the same as thatpreviously described with reference to FIGS. 3 to S of the drawings.

Variations in the required length of the jacking device under loadingconditions are accommodated by means of a third tubular member 18 whichis telescopically mounted within the lower end of the first tubularmember 14. The first tubular member 14 is formed with a narrow annularinwardly projecting waist por' tion 50 adjacentthe lower end thereof. Asimilar narrow inwardly projecting annular waist portion 52 is formedadjacent the upper end of the third tubular member 18. The third tubularmember 18 fits in a close fitting sliding relationship within the firsttubular member 14 and a pair of resilient sealing rings 54 are locatedwithin the recess provided by the waist portion 52. A compression coilspring 56 extends between the inwardly projecting waist portion 50 ofthe first tubular member 14 and the end 58 of the second tubular member.The spring 56 urges the third tubular member in a direction outwardly ofthe lower end of the first tubular member 14. The extent of movement ofthe third tubular member 18 outwardly from the end of the first tubularmember 14 is regulated by means of discs 62 and 64 and tie rod 66. Thedisc 62 is located inboard of the waist portion 50 and the disc 64 islocated inboard of the waist portion 52. The tie rod 66 passes throughdiscs 62 and 64 and nut 68 is locked on the end of the tie rod 66 tolimit the extent to which the discs 62 and 64 may move away from oneanother. The tie rod 66 is slidably mounted with respect to the disc 62so that when compressed the discs 62 and 64 may move towards one anotherto compress the spring 56 between the waist portion 50 and the end 58 aspreviously described.

The tubular members 14, 16 and 18 are preferably made from conventionaltubular steel. The adjusting device, including the bracket 30 and lever32, is preferably made from a high tensile steel capable of exertingsubstantial extending forces without deformation.

From the foregoing, it will be apparent that the present inventionprovides a simple and inexpensive form of jacking device which isparticularly suitable for use in the construction industry. The factthat the adjusting mechanism is detachable from telescoping members isof considerable importance as it renders the jacking devicesubstantially tamper proof. Without the jacking device it would bevirtually impossible for an individual to tamper with the adjustment.This is a significant factor in jacking devices of the present inventionwhen used to support safety railings as shown in FIG. 1 of the drawingson construction sites. In previous devices where the adjustmentmechanism is not removable, adjustments have been made by unauthorizedpersonnel which have resulted in failure of the jacking device.

Various modifications of the present invention will be apparent to thoseskilled in the art without departing from the scope of the invention.For example. the form of the locking mechanism for locking thetelescoping first and second tubular members in the extended positionmay be in the form of a releasable clamping screw or collar or the like.

From the foregoing, it will be apparent that the present inventionprovides a simple and inexpensive form of jacking device which can bevery easily adjusted to the required length.

The embodiments of the invention in which an exclusive property orprivilege is claimed are defined as follows:

1. A jacking device comprising a. a first tubular member,

b. a second tubular member telescopically mounted within said firsttubular member and projecting outwardly from one end of said firsttubular member,

c. adjustment means for adjusting the position of said second tubularmember with respect to said first tubular member,

d. said adjustment means consisting of a bracket member and a levermember, said bracket member having an inner end and an outer end,fulcrum means pivotally mounting said lever member with respect to saidbracket member with a first end of 0 said lever member projectingoutwardly from one side of said fulcrum means and a second end of saidlever member projecting outwardly from the other side of said fulcrummeans, said outer end of said bracket being adapted to engage said oneend of said first tubular member to support said bracket means in aposition with said fulcrum means spaced outwardly from said first andsecond tubular means,

e. a plurality of longitudinally spaced passages opening inwardly ofsaid second tubular member for engaging said first end of said leverwhereby said second tubular member may be telescoped with respect tosaid first member in response to movement of said second end of saidlever about said fulcrum means, and

f. means for locking said first tubular member with respect to saidsecond tubular member to prevent inward telescoping of said secondmember with respect to said first member.

2. A jacking device as claimed in claim 1 including slot means in saidone end of said first tubular member for receiving said outer end ofsaid bracket to secure said bracket against circumferential movementwith respect to said one end of said first tubular member.

3. A jacking device as claimed in claim 1 including collar means securedto said first tubular member at said one end thereof and projectingradially outwardly therefrom and cooperating with said end of said firsttubular member to provide a radially extending bracket support surface.

4. A jacking device as claimed in claim 3 including slot means in saidradially extending support surface for receiving said outer end of saidbracket to secure said bracket against circumferential movement withrespect to said first tubular member.

5. A jacking device as claimed in claim 2 wherein said outer end of saidbracket is formed to provide a pair of legs which are spaced apart adistance sufficient to be located on diametrically opposite sides ofsaid second tubular member, the outer ends of said legs being roundedfor pivotal engagement in said slot means.

6. A jacking device as claimed in claim 1 wherein said outer end of saidbracket is formed to provide a pair of legs which arespaced apart adistance sufficient to permit said means for locking said tubular memberto pass therebetween to engage said tubular members.

7. A jacking device as claimed in claim 3 wherein said bracket memberhas a bifurcated end for engaging said one end of said first tubularmember means at diametrically opposite sides of said first tubularmember, said lever means being pivotably connected to said bracket in aplane disposed between the bifurcated ends of said bracket whereby saidbifurcated ends form a stable support for said lever in use.

8. A jacking device asclaimed in claim 1 including a third tubularmember telescopically mounted within the other end of said first tubularmember for movement between a first retracted position and a secondextended position and means for resiliently urging said third tubularmember towards said extended position.

9. A jacking device as claimed in claim 8 wherein said second tubularmember is formed to provide a radially inwardly projecting annular waistportion adjacent said other end thereof, said means resiliently urgingsaid third portion towards said extended position comprising compressionspring having one end thereof bearing against said inwardly projectingwaist portion of said second tubular member and the other end bearingagainst the end of said third tubular member which is telescoped withinsaid first tubular member.

10. A jacking device as claimed in claim 9 wherein said third tubularmember is formed to provide a radially inwardly projecting waist portionadjacent the end thereof which is telescoped within said first tubularmember.

11. A jacking device as claimed in claim 10 including means forretaining said third tubular member in a telescoped relationship withrespect to said first tubular member comprising a pair of disc membersspaced from one another by said waist means of said first tubular memberand said waist means of said third tubular member, and tie rod meansextending between said first and second disc members.

1. A jacking device comprising a. a first tubular member, b. a secondtubular member telescopically mounted within said first tubular memberand projecting outwardly from one end of said first tubular member, c.adjustment means for adjusting the position of said second tubularmember with respect to said first tubular member, d. said adjustmentmeans consisting of a bracket member and a lever member, said bracketmember having an inner end anD an outer end, fulcrum means pivotallymounting said lever member with respect to said bracket member with afirst end of said lever member projecting outwardly from one side ofsaid fulcrum means and a second end of said lever member projectingoutwardly from the other side of said fulcrum means, said outer end ofsaid bracket being adapted to engage said one end of said first tubularmember to support said bracket means in a position with said fulcrummeans spaced outwardly from said first and second tubular means, e. aplurality of longitudinally spaced passages opening inwardly of saidsecond tubular member for engaging said first end of said lever wherebysaid second tubular member may be telescoped with respect to said firstmember in response to movement of said second end of said lever aboutsaid fulcrum means, and f. means for locking said first tubular memberwith respect to said second tubular member to prevent inward telescopingof said second member with respect to said first member.
 2. A jackingdevice as claimed in claim 1 including slot means in said one end ofsaid first tubular member for receiving said outer end of said bracketto secure said bracket against circumferential movement with respect tosaid one end of said first tubular member.
 3. A jacking device asclaimed in claim 1 including collar means secured to said first tubularmember at said one end thereof and projecting radially outwardlytherefrom and cooperating with said end of said first tubular member toprovide a radially extending bracket support surface.
 4. A jackingdevice as claimed in claim 3 including slot means in said radiallyextending support surface for receiving said outer end of said bracketto secure said bracket against circumferential movement with respect tosaid first tubular member.
 5. A jacking device as claimed in claim 2wherein said outer end of said bracket is formed to provide a pair oflegs which are spaced apart a distance sufficient to be located ondiametrically opposite sides of said second tubular member, the outerends of said legs being rounded for pivotal engagement in said slotmeans.
 6. A jacking device as claimed in claim 1 wherein said outer endof said bracket is formed to provide a pair of legs which are spacedapart a distance sufficient to permit said means for locking saidtubular member to pass therebetween to engage said tubular members.
 7. Ajacking device as claimed in claim 3 wherein said bracket member has abifurcated end for engaging said one end of said first tubular membermeans at diametrically opposite sides of said first tubular member, saidlever means being pivotably connected to said bracket in a planedisposed between the bifurcated ends of said bracket whereby saidbifurcated ends form a stable support for said lever in use.
 8. Ajacking device as claimed in claim 1 including a third tubular membertelescopically mounted within the other end of said first tubular memberfor movement between a first retracted position and a second extendedposition and means for resiliently urging said third tubular membertowards said extended position.
 9. A jacking device as claimed in claim8 wherein said second tubular member is formed to provide a radiallyinwardly projecting annular waist portion adjacent said other endthereof, said means resiliently urging said third portion towards saidextended position comprising compression spring having one end thereofbearing against said inwardly projecting waist portion of said secondtubular member and the other end bearing against the end of said thirdtubular member which is telescoped within said first tubular member. 10.A jacking device as claimed in claim 9 wherein said third tubular memberis formed to provide a radially inwardly projecting waist portionadjacent the end thereof which is telescoped within said first tubularmember.
 11. A jacking device as claimed in claim 10 including means forretaining said third tubular member in a telescoped relationship Withrespect to said first tubular member comprising a pair of discs membersspaced from one another by said waist means of said first tubular memberand said waist means of said third tubular member, and tie rod meansextending between said first and second disc members.